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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1254 AM CST Sun Nov 26 2023 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... ...Synopsis... An upper-level ridge will build over the Pacific Northwest, with a corresponding strengthening of surface high pressure over the Great Basin/Intermountain West. In response, the offshore pressure gradient will strengthen across southern California. Over portions of Los Angeles and Ventura Counties, breezy/gusty northeasterly surface winds and modest RH reductions could favor locally elevated fire-weather conditions. However, recent rainfall and the modest RH reductions should generally limit the fire-weather threat. Elsewhere across the CONUS, fire-weather concerns are minimal owing to cool and/or moist surface conditions. ..Weinman.. 11/26/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1254 AM CST Sun Nov 26 2023 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... ...Synopsis... An upper-level ridge will build over the Pacific Northwest, with a corresponding strengthening of surface high pressure over the Great Basin/Intermountain West. In response, the offshore pressure gradient will strengthen across southern California. Over portions of Los Angeles and Ventura Counties, breezy/gusty northeasterly surface winds and modest RH reductions could favor locally elevated fire-weather conditions. However, recent rainfall and the modest RH reductions should generally limit the fire-weather threat. Elsewhere across the CONUS, fire-weather concerns are minimal owing to cool and/or moist surface conditions. ..Weinman.. 11/26/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1254 AM CST Sun Nov 26 2023 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... ...Synopsis... An upper-level ridge will build over the Pacific Northwest, with a corresponding strengthening of surface high pressure over the Great Basin/Intermountain West. In response, the offshore pressure gradient will strengthen across southern California. Over portions of Los Angeles and Ventura Counties, breezy/gusty northeasterly surface winds and modest RH reductions could favor locally elevated fire-weather conditions. However, recent rainfall and the modest RH reductions should generally limit the fire-weather threat. Elsewhere across the CONUS, fire-weather concerns are minimal owing to cool and/or moist surface conditions. ..Weinman.. 11/26/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1254 AM CST Sun Nov 26 2023 Valid 261200Z - 271200Z ...NO CRITICAL AREAS... ...Synopsis... An upper-level ridge will build over the Pacific Northwest, with a corresponding strengthening of surface high pressure over the Great Basin/Intermountain West. In response, the offshore pressure gradient will strengthen across southern California. Over portions of Los Angeles and Ventura Counties, breezy/gusty northeasterly surface winds and modest RH reductions could favor locally elevated fire-weather conditions. However, recent rainfall and the modest RH reductions should generally limit the fire-weather threat. Elsewhere across the CONUS, fire-weather concerns are minimal owing to cool and/or moist surface conditions. ..Weinman.. 11/26/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CST Sun Nov 26 2023 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are unlikely on Tuesday. ...Synopsis... A cool and stable pattern will persist across the CONUS on Tuesday with a large upper trough over the East and a mean ridge over the Rockies. Dry conditions will be maintained over land due to strong offshore winds across the southeastern states, and an extensive area of high pressure. While a weak upper low is forecast to affect northern CA and western OR late Tuesday night, little to no instability is forecast to support nocturnal thunderstorms. ..Jewell.. 11/26/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CST Sun Nov 26 2023 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are unlikely on Tuesday. ...Synopsis... A cool and stable pattern will persist across the CONUS on Tuesday with a large upper trough over the East and a mean ridge over the Rockies. Dry conditions will be maintained over land due to strong offshore winds across the southeastern states, and an extensive area of high pressure. While a weak upper low is forecast to affect northern CA and western OR late Tuesday night, little to no instability is forecast to support nocturnal thunderstorms. ..Jewell.. 11/26/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CST Sun Nov 26 2023 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are unlikely on Tuesday. ...Synopsis... A cool and stable pattern will persist across the CONUS on Tuesday with a large upper trough over the East and a mean ridge over the Rockies. Dry conditions will be maintained over land due to strong offshore winds across the southeastern states, and an extensive area of high pressure. While a weak upper low is forecast to affect northern CA and western OR late Tuesday night, little to no instability is forecast to support nocturnal thunderstorms. ..Jewell.. 11/26/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CST Sun Nov 26 2023 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are unlikely on Tuesday. ...Synopsis... A cool and stable pattern will persist across the CONUS on Tuesday with a large upper trough over the East and a mean ridge over the Rockies. Dry conditions will be maintained over land due to strong offshore winds across the southeastern states, and an extensive area of high pressure. While a weak upper low is forecast to affect northern CA and western OR late Tuesday night, little to no instability is forecast to support nocturnal thunderstorms. ..Jewell.. 11/26/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CST Sun Nov 26 2023 Valid 281200Z - 291200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are unlikely on Tuesday. ...Synopsis... A cool and stable pattern will persist across the CONUS on Tuesday with a large upper trough over the East and a mean ridge over the Rockies. Dry conditions will be maintained over land due to strong offshore winds across the southeastern states, and an extensive area of high pressure. While a weak upper low is forecast to affect northern CA and western OR late Tuesday night, little to no instability is forecast to support nocturnal thunderstorms. ..Jewell.. 11/26/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CST Sat Nov 25 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... An isolated weak storm or two cannot be ruled out over far southern Florida on Monday. ...Synopsis/Discussion... A large-scale upper trough will amplify over the eastern CONUS on Monday, with a ridge over the West. This will maintain a stable pattern in terms of thunderstorm potential, with limited instability over land areas. The lone area of any potential will be over far southern FL, ahead of the cold front and around peak heating. Forecast soundings show sufficient instability for a few convective showers as the cold front undercuts the moist air mass. Any threat will be limited as dry air pushes in from the north. Elsewhere, a strong area of high pressure centered over the Great Basin and Plains will preclude any thunderstorm chances with offshore flow increasing over the Gulf Coast. ..Jewell.. 11/26/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CST Sat Nov 25 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... An isolated weak storm or two cannot be ruled out over far southern Florida on Monday. ...Synopsis/Discussion... A large-scale upper trough will amplify over the eastern CONUS on Monday, with a ridge over the West. This will maintain a stable pattern in terms of thunderstorm potential, with limited instability over land areas. The lone area of any potential will be over far southern FL, ahead of the cold front and around peak heating. Forecast soundings show sufficient instability for a few convective showers as the cold front undercuts the moist air mass. Any threat will be limited as dry air pushes in from the north. Elsewhere, a strong area of high pressure centered over the Great Basin and Plains will preclude any thunderstorm chances with offshore flow increasing over the Gulf Coast. ..Jewell.. 11/26/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CST Sat Nov 25 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... An isolated weak storm or two cannot be ruled out over far southern Florida on Monday. ...Synopsis/Discussion... A large-scale upper trough will amplify over the eastern CONUS on Monday, with a ridge over the West. This will maintain a stable pattern in terms of thunderstorm potential, with limited instability over land areas. The lone area of any potential will be over far southern FL, ahead of the cold front and around peak heating. Forecast soundings show sufficient instability for a few convective showers as the cold front undercuts the moist air mass. Any threat will be limited as dry air pushes in from the north. Elsewhere, a strong area of high pressure centered over the Great Basin and Plains will preclude any thunderstorm chances with offshore flow increasing over the Gulf Coast. ..Jewell.. 11/26/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CST Sat Nov 25 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... An isolated weak storm or two cannot be ruled out over far southern Florida on Monday. ...Synopsis/Discussion... A large-scale upper trough will amplify over the eastern CONUS on Monday, with a ridge over the West. This will maintain a stable pattern in terms of thunderstorm potential, with limited instability over land areas. The lone area of any potential will be over far southern FL, ahead of the cold front and around peak heating. Forecast soundings show sufficient instability for a few convective showers as the cold front undercuts the moist air mass. Any threat will be limited as dry air pushes in from the north. Elsewhere, a strong area of high pressure centered over the Great Basin and Plains will preclude any thunderstorm chances with offshore flow increasing over the Gulf Coast. ..Jewell.. 11/26/2023 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CST Sat Nov 25 2023 Valid 271200Z - 281200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... An isolated weak storm or two cannot be ruled out over far southern Florida on Monday. ...Synopsis/Discussion... A large-scale upper trough will amplify over the eastern CONUS on Monday, with a ridge over the West. This will maintain a stable pattern in terms of thunderstorm potential, with limited instability over land areas. The lone area of any potential will be over far southern FL, ahead of the cold front and around peak heating. Forecast soundings show sufficient instability for a few convective showers as the cold front undercuts the moist air mass. Any threat will be limited as dry air pushes in from the north. Elsewhere, a strong area of high pressure centered over the Great Basin and Plains will preclude any thunderstorm chances with offshore flow increasing over the Gulf Coast. ..Jewell.. 11/26/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1113 PM CST Sat Nov 25 2023 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk of severe thunderstorms appears negligible across the U.S., today through tonight. ...Discussion... Modestly amplified split westerlies near the North American Pacific coast converge across and east of the Rockies, where a pair of significant consolidating short wave troughs are forecast to contribute to the evolution of more prominent larger-scale troughing in the northern stream, as another short wave impulse digs across the central Canadian/U.S. border. As subtropical ridging centered over the Caribbean maintains strength as far north as the southeastern Gulf of Mexico and southern Florida Peninsula, models indicate considerable intensification of westerly flow between the large-scale troughing and ridging today through tonight. Within this regime, a focused area of strengthening upward vertical motion (supported by low-level warm advection beneath an increasingly divergent upper flow field) is forecast to continue to develop through daybreak today, near and south of Gulf coastal areas from southeastern Louisiana toward the Florida Big Bend. Coincident with further gradual modification of the north central and northeastern Gulf boundary layer, models suggest that destabilization may become supportive of an upscale growing convective cluster with embedded thunderstorm activity. It appears that this generally will become rooted above a residual stable boundary layer, to the north of a warm front in advance of a modest developing frontal wave, which likely will persist and overspread the Big Bend and adjacent portions of northern Florida through mid to late afternoon. Thereafter, a relatively compact, but stronger, surface cyclone is forecast to begin to develop offshore of the southern Mid Atlantic coast by early this evening, before migrating toward the Cape Cod vicinity through 12Z Monday. North-northwest of this feature, various model forecast soundings indicate the development of weak CAPE rooted within strengthening lower/mid-tropospheric warm advection. While this may be accompanied by an expanding area of convection across northern Mid Atlantic into New England coastal areas late this evening through the overnight hours, the extent to which this could become capable of producing lightning remains unclear. Due to at least initially limited low-level moisture return, and the lack of stronger forecast cooling aloft, thunderstorm probabilities still appear less than the minimum 10 percent threshold for a categorical thunder area at this time. ...Tampa Bay vicinity... Within the warm sector of the frontal wave, it is possible that hodographs could become supportive of potential for supercells with a risk of tornadoes along coastal areas near/north of Tampa Bay by late this afternoon. However, given lingering questions concerning the depth of the moistening boundary layer, and, particularly, a capping (relatively) warm layer centered around or just below the 500 mb level, unconditional severe probabilities still appear generally negligible (i.e., less than 2/5 percent for tornado/wind, respectively). ..Kerr/Weinman.. 11/26/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1113 PM CST Sat Nov 25 2023 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk of severe thunderstorms appears negligible across the U.S., today through tonight. ...Discussion... Modestly amplified split westerlies near the North American Pacific coast converge across and east of the Rockies, where a pair of significant consolidating short wave troughs are forecast to contribute to the evolution of more prominent larger-scale troughing in the northern stream, as another short wave impulse digs across the central Canadian/U.S. border. As subtropical ridging centered over the Caribbean maintains strength as far north as the southeastern Gulf of Mexico and southern Florida Peninsula, models indicate considerable intensification of westerly flow between the large-scale troughing and ridging today through tonight. Within this regime, a focused area of strengthening upward vertical motion (supported by low-level warm advection beneath an increasingly divergent upper flow field) is forecast to continue to develop through daybreak today, near and south of Gulf coastal areas from southeastern Louisiana toward the Florida Big Bend. Coincident with further gradual modification of the north central and northeastern Gulf boundary layer, models suggest that destabilization may become supportive of an upscale growing convective cluster with embedded thunderstorm activity. It appears that this generally will become rooted above a residual stable boundary layer, to the north of a warm front in advance of a modest developing frontal wave, which likely will persist and overspread the Big Bend and adjacent portions of northern Florida through mid to late afternoon. Thereafter, a relatively compact, but stronger, surface cyclone is forecast to begin to develop offshore of the southern Mid Atlantic coast by early this evening, before migrating toward the Cape Cod vicinity through 12Z Monday. North-northwest of this feature, various model forecast soundings indicate the development of weak CAPE rooted within strengthening lower/mid-tropospheric warm advection. While this may be accompanied by an expanding area of convection across northern Mid Atlantic into New England coastal areas late this evening through the overnight hours, the extent to which this could become capable of producing lightning remains unclear. Due to at least initially limited low-level moisture return, and the lack of stronger forecast cooling aloft, thunderstorm probabilities still appear less than the minimum 10 percent threshold for a categorical thunder area at this time. ...Tampa Bay vicinity... Within the warm sector of the frontal wave, it is possible that hodographs could become supportive of potential for supercells with a risk of tornadoes along coastal areas near/north of Tampa Bay by late this afternoon. However, given lingering questions concerning the depth of the moistening boundary layer, and, particularly, a capping (relatively) warm layer centered around or just below the 500 mb level, unconditional severe probabilities still appear generally negligible (i.e., less than 2/5 percent for tornado/wind, respectively). ..Kerr/Weinman.. 11/26/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1113 PM CST Sat Nov 25 2023 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk of severe thunderstorms appears negligible across the U.S., today through tonight. ...Discussion... Modestly amplified split westerlies near the North American Pacific coast converge across and east of the Rockies, where a pair of significant consolidating short wave troughs are forecast to contribute to the evolution of more prominent larger-scale troughing in the northern stream, as another short wave impulse digs across the central Canadian/U.S. border. As subtropical ridging centered over the Caribbean maintains strength as far north as the southeastern Gulf of Mexico and southern Florida Peninsula, models indicate considerable intensification of westerly flow between the large-scale troughing and ridging today through tonight. Within this regime, a focused area of strengthening upward vertical motion (supported by low-level warm advection beneath an increasingly divergent upper flow field) is forecast to continue to develop through daybreak today, near and south of Gulf coastal areas from southeastern Louisiana toward the Florida Big Bend. Coincident with further gradual modification of the north central and northeastern Gulf boundary layer, models suggest that destabilization may become supportive of an upscale growing convective cluster with embedded thunderstorm activity. It appears that this generally will become rooted above a residual stable boundary layer, to the north of a warm front in advance of a modest developing frontal wave, which likely will persist and overspread the Big Bend and adjacent portions of northern Florida through mid to late afternoon. Thereafter, a relatively compact, but stronger, surface cyclone is forecast to begin to develop offshore of the southern Mid Atlantic coast by early this evening, before migrating toward the Cape Cod vicinity through 12Z Monday. North-northwest of this feature, various model forecast soundings indicate the development of weak CAPE rooted within strengthening lower/mid-tropospheric warm advection. While this may be accompanied by an expanding area of convection across northern Mid Atlantic into New England coastal areas late this evening through the overnight hours, the extent to which this could become capable of producing lightning remains unclear. Due to at least initially limited low-level moisture return, and the lack of stronger forecast cooling aloft, thunderstorm probabilities still appear less than the minimum 10 percent threshold for a categorical thunder area at this time. ...Tampa Bay vicinity... Within the warm sector of the frontal wave, it is possible that hodographs could become supportive of potential for supercells with a risk of tornadoes along coastal areas near/north of Tampa Bay by late this afternoon. However, given lingering questions concerning the depth of the moistening boundary layer, and, particularly, a capping (relatively) warm layer centered around or just below the 500 mb level, unconditional severe probabilities still appear generally negligible (i.e., less than 2/5 percent for tornado/wind, respectively). ..Kerr/Weinman.. 11/26/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1113 PM CST Sat Nov 25 2023 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk of severe thunderstorms appears negligible across the U.S., today through tonight. ...Discussion... Modestly amplified split westerlies near the North American Pacific coast converge across and east of the Rockies, where a pair of significant consolidating short wave troughs are forecast to contribute to the evolution of more prominent larger-scale troughing in the northern stream, as another short wave impulse digs across the central Canadian/U.S. border. As subtropical ridging centered over the Caribbean maintains strength as far north as the southeastern Gulf of Mexico and southern Florida Peninsula, models indicate considerable intensification of westerly flow between the large-scale troughing and ridging today through tonight. Within this regime, a focused area of strengthening upward vertical motion (supported by low-level warm advection beneath an increasingly divergent upper flow field) is forecast to continue to develop through daybreak today, near and south of Gulf coastal areas from southeastern Louisiana toward the Florida Big Bend. Coincident with further gradual modification of the north central and northeastern Gulf boundary layer, models suggest that destabilization may become supportive of an upscale growing convective cluster with embedded thunderstorm activity. It appears that this generally will become rooted above a residual stable boundary layer, to the north of a warm front in advance of a modest developing frontal wave, which likely will persist and overspread the Big Bend and adjacent portions of northern Florida through mid to late afternoon. Thereafter, a relatively compact, but stronger, surface cyclone is forecast to begin to develop offshore of the southern Mid Atlantic coast by early this evening, before migrating toward the Cape Cod vicinity through 12Z Monday. North-northwest of this feature, various model forecast soundings indicate the development of weak CAPE rooted within strengthening lower/mid-tropospheric warm advection. While this may be accompanied by an expanding area of convection across northern Mid Atlantic into New England coastal areas late this evening through the overnight hours, the extent to which this could become capable of producing lightning remains unclear. Due to at least initially limited low-level moisture return, and the lack of stronger forecast cooling aloft, thunderstorm probabilities still appear less than the minimum 10 percent threshold for a categorical thunder area at this time. ...Tampa Bay vicinity... Within the warm sector of the frontal wave, it is possible that hodographs could become supportive of potential for supercells with a risk of tornadoes along coastal areas near/north of Tampa Bay by late this afternoon. However, given lingering questions concerning the depth of the moistening boundary layer, and, particularly, a capping (relatively) warm layer centered around or just below the 500 mb level, unconditional severe probabilities still appear generally negligible (i.e., less than 2/5 percent for tornado/wind, respectively). ..Kerr/Weinman.. 11/26/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1113 PM CST Sat Nov 25 2023 Valid 261200Z - 271200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk of severe thunderstorms appears negligible across the U.S., today through tonight. ...Discussion... Modestly amplified split westerlies near the North American Pacific coast converge across and east of the Rockies, where a pair of significant consolidating short wave troughs are forecast to contribute to the evolution of more prominent larger-scale troughing in the northern stream, as another short wave impulse digs across the central Canadian/U.S. border. As subtropical ridging centered over the Caribbean maintains strength as far north as the southeastern Gulf of Mexico and southern Florida Peninsula, models indicate considerable intensification of westerly flow between the large-scale troughing and ridging today through tonight. Within this regime, a focused area of strengthening upward vertical motion (supported by low-level warm advection beneath an increasingly divergent upper flow field) is forecast to continue to develop through daybreak today, near and south of Gulf coastal areas from southeastern Louisiana toward the Florida Big Bend. Coincident with further gradual modification of the north central and northeastern Gulf boundary layer, models suggest that destabilization may become supportive of an upscale growing convective cluster with embedded thunderstorm activity. It appears that this generally will become rooted above a residual stable boundary layer, to the north of a warm front in advance of a modest developing frontal wave, which likely will persist and overspread the Big Bend and adjacent portions of northern Florida through mid to late afternoon. Thereafter, a relatively compact, but stronger, surface cyclone is forecast to begin to develop offshore of the southern Mid Atlantic coast by early this evening, before migrating toward the Cape Cod vicinity through 12Z Monday. North-northwest of this feature, various model forecast soundings indicate the development of weak CAPE rooted within strengthening lower/mid-tropospheric warm advection. While this may be accompanied by an expanding area of convection across northern Mid Atlantic into New England coastal areas late this evening through the overnight hours, the extent to which this could become capable of producing lightning remains unclear. Due to at least initially limited low-level moisture return, and the lack of stronger forecast cooling aloft, thunderstorm probabilities still appear less than the minimum 10 percent threshold for a categorical thunder area at this time. ...Tampa Bay vicinity... Within the warm sector of the frontal wave, it is possible that hodographs could become supportive of potential for supercells with a risk of tornadoes along coastal areas near/north of Tampa Bay by late this afternoon. However, given lingering questions concerning the depth of the moistening boundary layer, and, particularly, a capping (relatively) warm layer centered around or just below the 500 mb level, unconditional severe probabilities still appear generally negligible (i.e., less than 2/5 percent for tornado/wind, respectively). ..Kerr/Weinman.. 11/26/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0649 PM CST Sat Nov 25 2023 Valid 260100Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk of thunderstorms appears negligible across much of the U.S. tonight. ...01Z Discussion... Despite modest ongoing low-level moisture return across the Texas coast into the southern Great Plains, destabilization has remained negligible due to the presence of relatively warm layers aloft with weak lapse rates. With stronger mid/upper support for upward vertical motion (associated with a short wave trough accelerating east-northeast of the southern Rockies) generally shifting across the central Great Plains toward the middle Mississippi Valley, little change appears likely through the remainder of this forecast period. Uncertainty lingers concerning the risk for thunderstorms closer to northwestern Gulf coastal areas, near/south of an intensifying subtropical jet axis. However, based on current trends, including the lack of more appreciable boundary-layer destabilization across the northwestern/north central Gulf of Mexico to this point, the risk for thunderstorms may remain generally negligible across all but, perhaps, areas near/south of Louisiana coastal areas through 12Z Sunday. ..Kerr.. 11/26/2023 Read more